My bad, can you try this instead? Basically we are trying to delete all "R, M, T" executions except the most recent 1000 of each type.
This is what the code is doing now, just really inefficiently for some reason -- and the inefficiency seems to have caused a "backlog" of sorts.
USE [BuildMaster]
BEGIN TRANSACTION
DELETE [Executions]
FROM [Executions] E,
(SELECT [Execution_Id],
ROW_NUMBER() OVER(PARTITION BY [ExecutionMode_Code] ORDER BY [Execution_Id] DESC) [Row]
FROM [Executions]
WHERE [ExecutionMode_Code] IN ('R', 'M', 'T')) EE
WHERE E.[Execution_Id] = EE.[Execution_Id]
AND EE.[Row] > 1000
SELECT [ExecutionMode_Code], COUNT(*) FROM [Executions] GROUP BY [ExecutionMode_Code]
ROLLBACK

). But it's still looking on track for early next year.
-- and a big thing we want to be improving in the next year, with both software and documentation changes.